{"id":"AZL-53067","summary":"CVE-2024-50229 affecting package kernel for versions less than 5.15.173.1-1","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnilfs2: fix potential deadlock with newly created symlinks\n\nSyzbot reported that page_symlink(), called by nilfs_symlink(), triggers\nmemory reclamation involving the filesystem layer, which can result in\ncircular lock dependencies among the reader/writer semaphore\nnilfs-\u003ens_segctor_sem, s_writers percpu_rwsem (intwrite) and the\nfs_reclaim pseudo lock.\n\nThis is because after commit 21fc61c73c39 (\"don't put symlink bodies in\npagecache into highmem\"), the gfp flags of the page cache for symbolic\nlinks are overwritten to GFP_KERNEL via inode_nohighmem().\n\nThis is not a problem for symlinks read from the backing device, because\nthe __GFP_FS flag is dropped after inode_nohighmem() is called.  However,\nwhen a new symlink is created with nilfs_symlink(), the gfp flags remain\noverwritten to GFP_KERNEL.  Then, memory allocation called from\npage_symlink() etc.  triggers memory reclamation including the FS layer,\nwhich may call nilfs_evict_inode() or nilfs_dirty_inode().  And these can\ncause a deadlock if they are called while nilfs-\u003ens_segctor_sem is held:\n\nFix this issue by dropping the __GFP_FS flag from the page cache GFP flags\nof newly created symlinks in the same way that nilfs_new_inode() and\n__nilfs_read_inode() do, as a workaround until we adopt nofs allocation\nscope consistently or improve the locking constraints.","modified":"2026-04-01T05:17:56.623848Z","published":"2024-11-09T11:15:08Z","upstream":["CVE-2024-50229"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2024-50229"}],"affected":[{"package":{"name":"kernel","ecosystem":"Azure Linux:2","purl":"pkg:rpm/azure-linux/kernel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"5.15.173.1-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-53067.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"}]}